The Effects of Rainforest Conversion on Water Balance, Water Yield and Seasonal Flows in a Small Tropical Catchment in C
The ongoing debate over the causes of deforestation in Indonesia views smallholder production and their growing number as a main cause of deforestation in Indonesia. With the common terminology ‘smallholder conversion’ a broad range of conversion strategi
- PDF / 1,598,673 Bytes
- 13 Pages / 439.37 x 666.142 pts Page_size
- 119 Downloads / 195 Views
1 Introduction The ongoing debate over the causes of deforestation in Indonesia views smallholder production and their growing number as a main cause of deforestation in Indonesia. With the common terminology 'smallholder conversion' a broad range of conversion strategies like the shifting cultivation-forest pioneer continuum, smallholder tree crop production and transmigration activities is summarized (Sunderlin and Resosudarmo, 1996). However, after 'smallholder conversion' the created landscape along the rainforest margin area is usually characterized by a patchwork of different land use types in ever smaller patches undergoing a gradual change from forest dominated areas via annual crops to perennial plantation interspersed by secondary forest, pasture and annual crops. Since the Indonesian economic crisis in 1997 land clearing increased dramatically for establishing export tree crops. Indonesia is now the third largest producer of cocoa (Sunderlin, 2000, Maertens et ai, 2002) with Central Sulawesi as one of the main Indonesian production areas. The question then arises: to what extent do these conversion activities affect the hydrological behaviour of the affected areas? In general, the role of forests in watershed hydrology and the effect of deforestation in the humid tropics on the hydrological response has been widely researched with respect to logging activities. With a few exceptions catchment experiments generally indicate increasec;Vrunoff from 'short-crop vegetation' with lower leaf area index and vegetation coverage compared with forested areas. Conversion impacts on seasonal flows are more difficult to predict. Different sitespecific, often competing, processes and causes can exist and the impact of land use change is therefore difficult to predict for a particular site (see Bruijnzeel 1990; Bosch and Hewlett 1982; Calder 2000). Within the framework of 'the stability of rainforest margins area project' (STORMA) in Indonesia an experimental catchment along the rainforest margin of the Lore Lindu National Park in Central Sulawesi has been designed in 2001 to generate scientific information about the influence of the unique transition process from natural forest to smallholder agroforestry on the hydrological cycle. The focus of this paper is to introduce the research area (Figure I) with its longterm research possibilities and give first hydrological characterizations and preG. Gerold et al. (eds.), Land Use, Nature Conservation and the Stability of Rainforest Margins in Southeast Asia © Springer-Verlag Berlin Heidelberg 2004
354
Alexander Kleinhans & Gerhard Gerold
liminary results of recent conversion effects on annual water yield and seasonal hydrological behaviour of the research area.
Instrumentation
,
A
rain gauge
~
climate station weir with water level recorder
river contour line (interval 50 m) river section (1,11,111) street and park boundary
175000
175500
176000
176500
Fig. 1. Location of the research area along the border of the Lore Lindu National Park in Central Sulawesi, I
Data Loading...
